Triplet state tetrylenes hold significant potential for transforming chemically inert substrates, but their fleeting nature has limited their detection to low-temperature environments. This challenge is amplified in heavier tetrylenes, such as germylenes, due to their higher singlet–triplet (S1–T1) energy gaps.
This work reports the photoinduced generation of a long-lived triplet germylene with a 14-hour half-life at room temperature, achieved through an excited singlet–triplet trap stabilization strategy.
The metastable nature of this excited state has enabled its spectroscopic investigation and the study of its reactivity. Enhanced reactivity compared to the ground state has been observed, including the cleavage of N=N, C–Br, Si–H bonds, and even the doubly reductive cleavage of C–C bonds in benzene.




